Variable capacity air conditioning system

ABSTRACT

A direct current (DC) powered variable capacity air conditioning system is provided. The system includes a plurality of temperature sensors for monitoring the temperature of various components, locations and air flows within the system. The system additionally includes an integrated controller board that substantially simultaneously controls a variable speed DC compressor motor, a variable speed condenser air mover and a variable speed evaporator air mover in response to inputs from the sensors. By substantially simultaneously controlling the variable speed DC compressor motor, the variable speed condenser air mover and the variable speed evaporator air mover, the system substantially simultaneously controls at least one of a temperature and a volume of an evaporator output air flow. Thus, the system provides a continuum of evaporator output air flow temperatures and capacities for maintaining an approximately constant temperature within an enclosed environment.

GOVERNMENT RIGHTS

This invention was made with Government support under contract DE-FC26-04NT42106, awarded by the United States Department of Energy. The Government may have certain rights in this invention.

FIELD

The present disclosure relates generally to temperature control systems and methods. More particularly, the present disclosure relates to a variable capacity DC environmental temperature control system and method.

BACKGROUND

Direct current (DC) environmental temperature control systems (ETCSs), also referred to as air conditioning systems, are often used to control the temperature within enclosed environments where alternating current (AC) ETCSs are not feasible, desirable or reliable. For example, in environments enclosed by structures that are remotely located where AC power is not available or conveniently accessible, or where a backup air conditioning system is necessary in case AC power is interrupted, or where a DC air conditioning system is more desirable than an AC air conditioning system. Generally, DC air conditioning systems have a capacity suitable for efficiently controlling the temperature of environments enclosed by smaller structures or buildings. For example, DC air conditioning systems are very suitable for controlling the temperature within utility sheds, portable or mobile structures, and electronics cabinets and utility or equipment structures such as cellular wireless communication electronic cabinets and battery backup closets.

Such smaller structures can be located in a wide variety of outdoor locations that present a myriad of rigorous exterior environmental conditions that affect the temperature within the structures. That is, the structures can be exposed to a wide range of external temperatures, e.g., −30° C. to 55° C. (−22° F. to 131° F.), varying solar loads and various forms of precipitation that can all affect the internal environmental temperature. In the case of equipment cabinets, temperature control requirements can be stringent in order to prevent damage to the often expensive and not terribly rugged equipment inside. Thus, employment of DC air conditioning systems is often desirable for actively controlling the temperature enclosed environment of such smaller structures. And in many cases, efficiency, consistency and reliability are critical necessities of the DC air conditioning system.

In most instances, DC air conditioning systems are designed as typical expansion-compression heating and cooling systems that include a heating mechanism, a compressor, a condenser subsystem and an evaporator subsystem. Generally, operation of the heating mechanism is controlled by a heating mechanism controller, operation of the compressor is controlled by a compressor controller, operation of the condenser sub-system is controlled by a condenser controller and operation of the evaporator subsystem is controlled by an evaporator controller. Each of the controllers turns the respective components/subsystems ‘On’ or ‘Off’, based on a set point temperature signal received from a thermostat. Therefore, if the temperature of the enclosed environment rises a predetermined amount above the set point, the compressor controller, condenser subsystem controller and evaporator subsystem controller turn ‘On’ the respective components/subsystems.

When the temperature is brought within the set point range, the respective controllers turn the respective components/subsystems ‘Off’. Similarly, if the temperature of the enclosed environment drops a predetermined amount below the set point, the heating mechanism controller will turn the heating mechanism ‘On’ until the temperature rises to be within the set point range, at which point the heating mechanism controller shuts the heating mechanism ‘Off’. Additionally, when the respective controllers turn the respective components/subsystems ‘On’, the components/subsystems operate and full speed or full capacity. Likewise, when the respective controllers turn the respective components/subsystems ‘Off’, the components/subsystems do not operate. Accordingly, the DC air conditioning system enters a duty cycle turning the components/subsystems ‘On’ when the enclosed environment temperature is outside the set point range and ‘Off’ once the temperature is brought back within the set point range.

Thus, typical DC air conditioning systems include numerous separate, independent controllers, mounted at various locations within the DC air conditioning system, for controlling each of the components/subsystems and have a single capacity, whereby the components/subsystems are either ‘On’ or ‘Off’.

BRIEF SUMMARY

In various embodiments, a direct current (DC) powered variable capacity air conditioning system is provided. The system includes a plurality of temperature sensors for monitoring the temperature of various components, locations and air flows within the system. The system additionally includes an integrated controller board that substantially simultaneously controls a variable speed DC compressor motor, a variable speed condenser air mover and a variable speed evaporator air mover in response to inputs from the sensors. By substantially simultaneously controlling the variable speed DC compressor motor, the variable speed condenser air mover and the variable speed evaporator air mover, the system substantially simultaneously controls at least one of a temperature and a volume of an evaporator output air flow. Thus, the system provides a continuum of evaporator output air flow temperatures and capacities for maintaining an approximately constant temperature within an enclosed environment.

Further areas of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating various preferred embodiments, are intended for purposes of illustration only and are not intended to limit the scope of the disclosure. Additionally, the features, functions, and advantages of the present disclosure can be achieved independently in various embodiments or may be combined in yet other embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from the detailed description and accompanying drawings, wherein;

FIG. 1 is a block diagram of a direct current (DC) powered variable capacity air conditioning system (VCACS) connected to a structure enclosing an environment to be thermally conditioned by the variable capacity air conditioning system, in accordance with various embodiments;

FIG. 2 is a schematic illustration of the VCACS shown FIG. 1, in accordance with various embodiments;

FIG. 3 is an exploded isometric view of the VCACS illustrating various components of the VCACS, in accordance with various embodiments;

FIG. 4 is a side view of the VCACS shown in FIG. 1 with a side removed to illustrate components within the VCACS, in accordance with various embodiments;

FIG. 5 is a front view of the VCACS shown in FIG. 1 with an evaporator air mover cover removed, in accordance with various embodiments;

FIG. 6 is a rear view of the VCACS shown in FIG. 1 with a back removed to illustrate components of a condenser assembly, in accordance with various embodiments; and

FIG. 7 is a state diagram illustrating a temperature dependent operation of the VCACS shown in FIG. 1, in accordance with various embodiments.

Corresponding reference numerals indicate corresponding parts throughout the several views of drawings.

DETAILED DESCRIPTION

The following descriptions of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the present disclosure, its application or uses. Additionally, the advantages provided by the preferred embodiments, as described below, are exemplary in nature and not all preferred embodiments provide the same advantages or the same degree of advantages.

FIG. 1 illustrates a direct current (DC) powered variable capacity air conditioning system 10 connected to a wall of a structure 14 enclosing an environment 18 to be thermally conditioned by the variable capacity air conditioning system (VCACS) 10. The DC VCACS 10 can operate any suitable power rating using any suitable DC power supply (not shown) such as one or more DC batteries or a converted alternating current (AC) supply. In various embodiments the DC VCACS 10 is configured to operate at a power rating of between approximately 1.25 kW and 2.25 kW, e.g., 1.75 kW.

The structure 14 can be any building, shed, cabinet, closet, portable or mobile structure, or any other structure enclosing an environment desirous of being thermally controlled by the DC variable capacity air conditioning system 10. For example, the structure 14 can be an electronics and/or equipment cabinet, such as a cellular wireless communication electronics cabinet or battery backup closet, where it is important to maintain the enclosed environment 18 at a desired temperature to prevent damage to the enclosed components and/or systems. The VCACS 10 is configured to provide heating and cooling to maintain a substantially constant temperature of the enclosed environment 18 of the structure 14. More particularly, in various embodiments, the VCACS 10 provides active variable heating and cooling capacity to the environment 18 enclosed by the structure 14. As used herein, the phrase ‘active variable heating and cooling capacity’ means that the temperature of the enclosed temperature controlled environment 18 can be greater than or less than that of the surrounding exterior ambient conditions of the structure 14. In various exemplary embodiments, the VCACS 10 and the structure 14 can comprise a telecommunication station, e.g., a wireless telecommunication station, wherein the structure 14 is a telecommunication electronics and equipment cabinet.

The VCACS 10 generally includes a heating subsystem, generally indicated at 22, a cooling subsystem, generally indicated at 26, and an integrated controller board 30 that controls the functionality and operation of the heating and cooling subsystems 22 and 26. The cooling subsystem 26 generally comprises a condenser assembly 34, an evaporator assembly 38 and a DC variable speed compressor 42 connected to the condenser and evaporator assemblies 34 and 38 via refrigerant lines 46. As described herein, a system refrigerant flows through the refrigerant lines 46 during operation of the cooling subsystem 26, changing between various gaseous and liquid states. The heating subsystem 22 generally comprises at least one heating mechanism 50 and various components of the evaporator assembly 38, as described below. The heating mechanism(s) 50 can be any suitable heat producing mechanism such as an open wire resistive heater, a ceramic resistive heater, radiator type heater, a chemical reaction type heater, or any other heating device, assembly or system. In various embodiments, the heating mechanism(s) 50 is/are variable output positive temperature coefficient heater(s) controlled by the integrated controller board 30 substantially simultaneously with the variable speed evaporator air mover 70. Particularly, the integrated controller board 30 can vary the heat capacity of the heaters to match the needed load.

Referring now to FIG. 2, the condenser assembly 34 generally includes a condenser heat exchanger 54, a variable speed condenser air mover 58 and a condenser air filter 62. The evaporator assembly 38 generally includes an evaporator heat exchanger 66 and a variable speed evaporator air mover 70. The condenser heat exchanger 54 is connected in-line with the refrigerant lines 46 between the compressor 42 and the evaporator heat exchanger 66. More particularly, the condenser heat exchanger 54 is connected at a condenser refrigerant inlet 74 to a portion of the refrigerant lines 46 from the compressor 42 and at a condenser refrigerant outlet 78 to a portion of the refrigerant lines 46 leading to the evaporator heat exchanger 66. High pressure superheated refrigerant vapor enters the condenser heat exchanger 54 at the condenser refrigerant inlet 74 and flows through the condenser heat exchanger 54. As the superheated refrigerant vapor flows through the condenser heat exchanger 54, it is cooled and converted to a subcooled liquid by a condenser air flow 82 across or through the condenser heat exchanger 54, as controlled by the integrated controller board 30, as described below. The condenser air flow 82 comprises air entering the VCACS 10 from the exterior ambient environment of the VCACS 10 and the structure 14. The high pressure converted liquid refrigerant then exits the condenser heat exchanger 54 at the condenser refrigerant outlet 78.

The high pressure liquid refrigerant flows through a standard filter/drier 86 and enters a thermally controlled expansion valve (TXV) 90. The TXV 90 controls the flow of refrigerant therethrough such that the high pressure liquid refrigerant is converted to a low pressure saturated liquid-gas having a temperature significantly lower than the high pressure liquid refrigerant exiting the condenser refrigerant outlet 78. In various embodiments, the TXV 90 is a conventional type TXV that is independently controlled. In various other embodiments, the TXV 90 is a stepper-motor style electronically variable expansion valve controlled by the integrated controller board 30 based on a sensed temperature of the refrigerant exiting the evaporator heat exchanger 66 and the sensed temperature of the refrigerant entering the evaporator heat exchanger 66.

The evaporator heat exchanger 66 is connected in-line with the refrigerant lines 46 between the TXV 90 and the compressor 42. More particularly, the evaporator heat exchanger 66 is connected at an evaporator refrigerant inlet 94 to a portion of the refrigerant line 46 from the TXV 90 and at an evaporator refrigerant outlet 98 to a portion of the refrigerant line 46 leading to the compressor 42. The low pressure refrigerant saturated liquid vapor mixture enters the evaporator heat exchanger 66 at the evaporator refrigerant inlet 94 and flows through the evaporator heat exchanger 66. As the refrigerant vapor flows through the evaporator heat exchanger 66, it absorbs heat from an evaporator air flow 102 across or through the evaporator heat exchanger 66 as controlled by the integrated controller board 30, as described below, and is converted to a low pressure superheated gaseous state. The evaporator air flow 102 comprises air entering the VCACS 10 from the enclosed temperature controlled environment 18, as described further below. The low pressure superheated gaseous refrigerant exits the evaporator heat exchanger 66 at the evaporator refrigerant outlet 78 and flows to the compressor 42. The compressor 42 then compresses the low pressure superheated gaseous refrigerant to the high pressure superheated gaseous refrigerant input to the condenser heat exchanger 54, and the cycle described above is repeated.

The condenser air mover 58 can be any air mover suitable for moving varying capacities of air, as controlled by the integrated controller board 30, from the exterior ambient environment, through the condenser assembly 34 and back into the exterior ambient environment. For example, the condenser air mover 58 can be a radial fan, an axial fan or a turbine. In various embodiments, the condenser air mover 58 is a variable speed backward-curved impeller. Similarly, the evaporator air mover 70 can be any air mover suitable for moving varying capacities of air, as controlled by the integrated controller board 30, from the enclosed environment 18, through the evaporator assembly 38 and back into the enclosed environment 18. For example, the evaporator air mover 70 can be a radial fan, an axial fan or a turbine. In various embodiments, the evaporator air mover 70 is a variable speed backward-curved impeller. The condenser air filter 62 can be any air filter suitable for effectively preventing particulate matter such as airborne dust, dirt, leaves, grass, weeds, insects, etc. from infiltrating the condenser assembly 34.

As illustrated in FIG. 2, and described in further detail below, the integrated controller board 30 receives inputs 106 from a plurality of temperature sensors 110 located within the VCACS 10 and the structure 18. Additionally, in various embodiments, the integrated controller board 30 receives at least one input 106 from at least one relative humidity sensor 112 located within the air flow 102 output by the evaporator assembly 38 for sensing a humidity level of the air flow 102 output to enclosed environment 18. During a cooling mode of operation of the VCACS 10, in which the VCACS 10 cools the enclosed environment 18, the integrated controller board 30 utilizes the inputs 106 from the sensors 110 and 112 to substantially simultaneously control the variable speed condenser air mover 58, the variable speed evaporator air mover 70, the variable speed compressor 42 and a compressor heater 108. Similarly, during a heating mode of operation, in which the VCACS 10 heats the enclosed environment, the integrated controller board 30 utilizes the inputs 106 from the sensors 110 and 112 to substantially simultaneously control the variable speed evaporator air mover 70 and the heating mechanism(s) 50.

In various embodiments, the sensors 110 include an evaporator air intake sensor 110A, an evaporator refrigerant inlet sensor 110B, an evaporator refrigerant outlet sensor 110C, a condenser refrigerant outlet sensor 110D, a condenser air intake sensor 110E, a compressor housing temperature sensor 110F, a heat sink temperature sensor 110G, and at least one remote temperature sensor 110H. For simplicity and clarity of FIG. 2, the sensors 110 and 112 are not shown directly connected to the integrated controller board inputs 106. However, it should be understood that the various temperature signals generated by the various sensors 110 are received by the integrated controller board 30 at the inputs 106.

The evaporator air intake sensor 110A senses the temperature of evaporator air flow 102 taken into the evaporator assembly 38 from the enclosed environment 18. In various embodiments, the evaporator air intake sensor 110A is the main sensor 110 used by the integrated controller board 30 for determining the temperature within the enclosed environment 18. Furthermore, it is the sensed temperature of the enclosed environment 18 that the integrated controller board 30 utilizes to substantially simultaneously control operation of the cooling subsystem 26 components and the heating subsystem 22 components to actively maintain approximately a desired temperature of the enclosed environment 18. The evaporator refrigerant inlet sensor 110B senses the temperature of the system refrigerant at the evaporator refrigerant inlet 94 and the evaporator refrigerant outlet sensor 110C senses the temperature of the system refrigerant at the evaporator refrigerant outlet 98. The condenser refrigerant outlet sensor 110D senses the temperature of the system refrigerant at condenser outlet 78. The condenser air intake sensor 110E senses the temperature of condenser air flow 82 taken into the condenser assembly 34 from the exterior ambient environment. The compressor housing temperature sensor 110F senses the temperature of a variable speed DC compressor motor 114 controlled by the integrated controller board 30 to control operation of the compressor 42. The variable speed DC compressor motor 114 operates using power from the DC power supply and can drive the compressor 42 at significantly varying rates to displace varying rates of the system refrigerant at varying rates of compression.

In various embodiments, the compressor motor 114 is a brushless sensorless permanent magnet DC motor and the compressor 42 is a scroll compressor in a hermitically sealed enclosure. However, the compressor motor 114 and compressor 42 can be any motor/compressor combination suitable for increasing the system refrigerant pressure within the refrigerant lines 46 in accordance with commands from the integrated controller board 30. The heat sink temperature sensor 110G senses the temperature of a heat sink 118 of the integrated controller board 30. And, the remote temperature sensor(s) 110H sense(s) the temperature within the enclosed environment at one or more locations other than at the point the evaporator air flow 102 is taken into the evaporator assembly 38 from the enclosed environment, as sensed by intake sensor 110A. In various embodiments, the remote sensor(s) 110H are used to input the sensed temperature within the enclosed environment 18 that the integrated controller board 30 utilizes to substantially simultaneously control operation of the cooling subsystem 26 components and the heating subsystem 22 components to actively maintain approximately a desired temperature of the enclosed environment. In various other embodiments, the integrated controller board 30 utilizes a combination of inputs from the evaporator air intake sensor 110A and the remote sensor(s) 110H to substantially simultaneously control operation of the cooling subsystem 26 components and the heating subsystem 22 components to actively maintain approximately a desired temperature of the enclosed environment.

Still referring to FIG. 2, in various embodiments, the integrated controller board 30 includes a DC power supply bus 120, a processor 122, e.g., a microprocessor, and at least one electronic storage device 126. The processor 122 can be any processor suitable to execute all functions of integrated controller board 30. The electronic storage device(s) 126 can be any computer readable medium suitable for electronically storing such things as data, information, algorithms and/or software programs executable by the processor 122. For example, in various embodiments, the electronic storage device(s) 126 can be memory device(s) such a hard drive, EEPROM, Flash Memory, OTP memory or any other electronic data storage device or medium. In various other embodiments, the electronic storage device(s) 126 can be remotely located from the controller board 30. Furthermore, in various embodiments the electronic storage device(s) 126 can be removably connectable to the integrated controller board 30. For example, the electronic storage device(s) 126 can be a USB hard drive, a Zip drive disk, a CDRW drive disk, a DVDR drive disk, a thumb drive or any other removable electronic storage device.

Further yet, in various embodiments, the integrated controller board 30 includes an input device 130, such as a keypad, a mouse, a stylus or a joy stick for inputting data and information to the integrated controller board to be stored on the electronic memory device 126. Still further yet, in various embodiments, the integrated controller board 30 includes a display 134 for illustrating graphical and/or textual/numeric data and various other forms of information. Still even further yet, in various embodiments, the integrated controller board 30 can be wired or wirelessly connected or connectable to a remote computer based system. For example, the integrated controller board 30 can be wired or wirelessly connected or connectable to a remotely located server system (not shown), such that data, information, algorithms, VCACS 10 operational commands, software programs, or any other data can be communicated to and/or from the integrated controller board 30.

To substantially simultaneously control the operation of the components of the cooling subsystem 26 during the cooling mode and substantially simultaneously control operation of the components of the heating subsystem 22 during the heating mode, the integrated controller board 30 further includes a plurality of VCACS component controllers 138. For example, in various embodiments, the integrated controller board 30 includes a condenser air mover controller 138A for controlling operation of the condenser air mover 58, an evaporator air mover controller 138B for controlling the operation of the evaporator air mover 70 and a variable speed compressor motor controller 138C for controlling operation of the variable speed compressor motor 114. Each of the various controllers 138 are mounted on the integrated controller board 30 and can be substantially simultaneously controlled by the processor 122. More particularly, the processor 122 executes one or more control software programs and/or algorithms to substantially simultaneously control operation of the various controllers 138 to operate the VCACS 10 in the cooling mode and the heating mode. For example, the processor 122 receives the inputs from the temperature sensor 110 and the relative humidity sensor(s) 112, then executes one or more control algorithms to substantially simultaneously control operation of the variable speed condenser air mover controller 138A, the variable speed evaporator air mover controller 138B and the variable speed DC compressor motor controller 138C, based on the inputs.

Accordingly, the speed at which the condenser air mover 58, the evaporator air mover 70 and the compressor motor 114 operate are substantially simultaneously controlled by the processor 122, based on the various inputs 106, to dynamically control the output capacity of the VCACS 10. That is, the temperature and/or volume of the evaporator air flow 102 output by the VCACS 10, are substantially simultaneously dynamically controlled by the processor 122 substantially simultaneously controlling the speed at which the condenser air mover 58, the evaporator air mover 70 and the compressor motor 114 operate, based on the various inputs 106. Thus, a capacity and temperature continuum of evaporator assembly 38 output air flow 102 is provided for maintaining an approximately constant temperature within the enclosed environment 18. More particularly, the execution of one or more control algorithms seamlessly transitions operation of the VCACS 10 from the cooling mode to the heating mode, if the temperature within the enclosed environment 18 falls below a desired cooling set point, as described below. Similarly, the execution of the single control algorithm can seamlessly transition operation of the VCACS 10 from the heating mode to the cooling mode, if the temperature within the enclosed environment 18 rises above a desired heating set point, as described below.

In various embodiments, the processor 122 executes a single control algorithm to substantially simultaneously control operation of the various controllers 138 to operate the VCACS 10 in the cooling and heating modes based on the inputs from the sensors 110 and 112.

Referring now to FIGS. 3, 4, 5 and 6, in various embodiments, the VCACS 10 is constructed about a main skeletal support structure 142. The skeletal support structure 142 generally includes a condenser assembly support frame 146 and an evaporator assembly support frame 150 mounted to, e.g., welded, bolted, or integrally formed with, a base plate 154. The condenser and evaporator assemblies 34 and 38 are mounted to the respective condenser and evaporator assembly supports 146 and 150. The variable speed compressor 42, including the variable speed motor 114, is mounted to the base plate 154 between the condenser and evaporator assemblies 34 and 38. The evaporator assembly 38 includes an evaporator shroud 158 coupled to the evaporator assembly support frame 150. In various embodiments, the evaporator shroud 158 is formed or fabricated as a single piece, seamless structure. For example, the evaporator shroud 158 can be molded, cast, stamped or pressed to form a three-dimensional monolithic structure without folded or bent edges, joint seams or cracks that require sealing with a sealant, e.g., an RTV sealant. The evaporator shroud 158 can be fabricated from any suitable material such as any suitable plastic polymer or composite, any suitable reinforced polyurethane or epoxy resin or any other material suitable for fabricating a three-dimensional monolithic evaporator shroud 158. Additionally, the evaporator shroud 158 effectively forms a walled enclosure within the VCACS 10 enclosing the remaining evaporator assembly components therewithin and separating the evaporator assembly 38 from the condenser assembly 34.

The evaporator heat exchanger 66 and heating mechanism 50 are mounted within a lower portion of the evaporator shroud 158. The evaporator air mover 70 is mounted within an upper portion of the evaporator shroud 158 and the integrated controller board is mounted within a center portion of the evaporator shroud 158. In various embodiments, the evaporator air mover 70 is rotationally mounted to an evaporator air mover mounting plate 162 that is mounted to the evaporator shroud 158. A housing panel 166 is mounted over the evaporator air mover 70, evaporator heat exchanger 66, heating mechanism 50 and integrated controller board 30 and coupled to the evaporator shroud 158 and/or a housing hood 170. The housing panel includes an evaporator air intake opening 174 and a plurality of grated or finned apertures that generally form an evaporator air output opening 178. The combination of the housing panel 166 mounted over the evaporator shroud 158 form an evaporator air passage 182, best illustrated in FIG. 4. Thus, the integrated controller board 30 is mounted within the evaporator air passage 182 such that the evaporator air flow 102 assists in cooling components on the integrated controller board 30, e.g., power electronics that drive the compressor motor 114.

An evaporator air intake cover assembly 190 is mounted to the housing panel 166 over the evaporator air intake opening 174. In various embodiments, the evaporator air intake cover assembly 190 includes a screen 194 mounted to an evaporator air mover cover 198 over an air mover cover aperture 198. The screen 194 and aperture 198 allow the air flow 102 from the enclosed environment 18 to be taken or drawn into the evaporator air passage 182 by the evaporator air mover 70, as described above. When the evaporator air mover 70 is operating, e.g., in the heating mode, the cooling mode and an idle mode, the evaporator air flow 102 is drawn into the evaporator air passage 182 from the enclosed environment 18, via the evaporator air mover cover aperture 202 and the evaporator air intake opening 174. As the evaporator air flow 102 flows through the evaporator air passage 182, the evaporator air flow 102 can be conditioned, i.e., heated or cooled as described herein, and output back into the enclosed environment 18, via the evaporator air output opening 178. When the VCACS 10 is operating in the idle mode, the evaporator air flow 102 is circulated through the evaporator air passage 182, as described above, but is not heated or cooled. Thus, the air within the enclosed environment 18 is circulated but not temperature conditioned by the VCACS 10.

The condenser assembly 34 includes a condenser shroud 206 coupled to the condenser assembly support frame 146. In various embodiments, the condenser shroud 206 is formed or fabricated as a single piece, seamless structure. For example, the condenser shroud 206 can be molded, cast, stamped or pressed to form a three-dimensional monolithic structure without folded edges or joint seams. The condenser shroud 206 can be fabricated from any suitable material such as any suitable plastic polymer or composite, any suitable reinforced polyurethane or epoxy resin or any other material suitable for fabricating a three-dimensional monolithic condenser shroud 206. The condenser air mover 58 is mounted within the condenser shroud 206 and a condenser shroud cover 210 is mounted to the condenser shroud 206 over the condenser air mover 58. In various embodiments, the condenser air mover 58 is rotationally mounted to a condenser air mover mounting plate 214 that is mounted to the condenser shroud 206. The condenser heat exchanger 54 is mounted to the condenser assembly support frame 146 below the condenser shroud 206. The air intake filter 62 is positioned over, or within, the condenser shroud cover 210 for filtering particulates from the condenser intake air flow 82.

The housing hood 170 is mounted over the condenser shroud 206, the condenser air mover, shroud cover and filter 58, 210 and 62, and the condenser heat exchanger 54, and coupled to the housing panel 166. It should be understood that although the housing hood 170 is referred to herein as a single structure, the housing hood 170 can be constructed of one or more panels, e.g., side panels, top panel and/or front panel. The housing hood 170 includes a condenser air intake opening 222 and a plurality of grated or finned apertures that generally form a condenser air output opening 226. A condenser air intake cover 230, including a plurality of grated or finned apertures that generally form an air intake cover opening 232, is mounted to the housing hood 170 to cover the condenser air intake opening 222. When the condenser air mover 58 is operating, e.g., in the heating and cooling modes, the condenser air flow 82 is drawn into the condenser shroud 206 from the exterior ambient environment. The condenser shroud is fabricated to have an open bottom such that the condenser air flow 82 drawn in is circulated through the condenser shroud 206 and down through the VCACS 10 behind the evaporator shroud 158. The condenser air flow 82 then flows through the condenser heat exchanger 54 and is output back into the exterior ambient environment, via the condenser air output opening 226. Accordingly, the condenser air flow 82 is circulated through the VCACS 10 and around, or across, the variable speed compressor motor and compressor 114 and 42, thereby cooling the variable speed compressor motor and compressor 114 and 42.

Referring again to FIG. 2, in the event that the VCACS 10 has been non-operational, i.e., newly installed and not yet turned on, the internal temperature of the enclosed environment 18 can be considerably hotter than the temperature of the external ambient environment. In this scenario, extreme pressures can build within the refrigerant lines 46, the condenser and evaporator heat exchangers 54 and 66, and the compressor 42 due to the superheat phases of the refrigerant becoming excessive as the condenser heat exchanger 54 is unable to reject heat to the outdoor ambient as quickly as the evaporator heat exchanger 66 is able to absorb heat from the enclosed environment 18. To avoid damaging the VCACS 10, in various embodiments, the processor 122 executes a start-up algorithm, or a start-up subroutine of the control algorithm. The start-up algorithm or subroutine interprets the various inputs 106 from the sensors 110 and 112 and, if necessary, reduces the speed of the evaporator air mover 70 so that less heat is removed from evaporator air flow 102. This allows the condenser assembly 34 to ‘catch up’, i.e., the evaporator heat exchanger 66 absorbs less heat while the condenser heat exchanger 54 rejects heat at a maximum capacity, until the superheat phases of the refrigerant are maintained at a desirable level.

As described above, the air temperature within the enclosed environment 18 is the primary input utilized by the controller board 30 to control the VCACS 10, that is, to dynamically control the temperature and/or volume of the evaporator air flow 102 output to the enclosed environment 18. In various exemplary embodiments, the one or more control algorithms executed by the processor 122 utilizes the input 106 from the evaporator air inlet sensor 110A and/or the input 106 from the remote sensor(s) 110H to determine the temperature within the enclosed environment 18. Based on the input(s) 106 from the evaporator air inlet sensor 110A and/or the remote sensor(s) 110H, the integrated controller board 30 determines the VCACS 10 should be in the heating mode, cooling mode or idle mode. If the integrated controller board 30 determines the heating mode is required, the integrated controller board 30 turns ‘On’ the heating mechanism(s) 50 and evaporator air mover 70. The heat level of the heating mechanism(s) 50 and the speed of the evaporator air mover 70 are then substantially simultaneously controlled by the integrated controller board 30 to dynamically vary the temperature and/or volume of the evaporator air flow 102 output to the enclosed environment 18.

If the integrated controller board 30 determines the cooling mode is required, the integrated controller board 30 turns on the compressor motor 114, the condenser air mover 58 and the evaporator air mover 70. The integrated controller board 30 then substantially simultaneously controls the speed of the compressor motor 114, the speed of the condenser air mover 58 and the speed of the evaporator air mover 70 to dynamically vary the temperature and/or volume of the evaporator air flow 102 output to the enclosed environment 18. If the integrated controller board 30 determines the idle mode is required, the integrated controller board turns ‘Off’ the heating mechanism(s) 50 or the compressor motor 114 and condenser air mover 58. Additionally, in the idle mode the integrated controller board 30 either turns the evaporator air mover 70 ‘off’ also, or leaves the evaporator air mover 70 running. If the evaporator air mover 70 remains running, the integrated controller board 30 controls the speed to dynamically vary the volume of the evaporator air flow 102 output to the enclosed environment 18. Varying temperature and/or volume of the continuum of evaporator air flow 102 output to the enclosed environment 18, as the VCACS 10 seamlessly transitions between the heating, cooling and idle modes, maintains the enclosed environment 18 at approximately the desired temperature.

Although the various embodiments are described herein in terms of the integrated controller board 30 having a direct affect on, or direct control of, the VCACS 10, it should be understood that it is the instructions generated by the execution of the one or more algorithms, via the processor 122 and the subsequent implementation of those instructions by the integrated controller board that have direct effect on, or control of, the VCACS 10.

Referring now to FIG. 7, a state diagram 300 illustrates a temperature dependent operation of the VCACS 10, in accordance with various embodiments. As described above, upon turning ‘On’ the VCACS 10 from a non-operational state, the evaporator air mover 70 is turned ‘On’, and the processor 122 executes the start-up algorithm, or a start-up subroutine of the control algorithm. The start-up algorithm or subroutine interprets the various inputs 106 from the sensors 110 and 112 and, if necessary, adjusts the speed of the evaporator air mover 70 until the condenser assembly 34 ‘catches up’, i.e., the evaporator heat exchanger 66 absorbs less heat while the condenser heat exchanger 54 rejects heat at a maximum capacity, until the superheat phases of the refrigerant are maintained at a desirable level. The exemplary description of the operation of the VCACS 10, with respect to state diagram 300, will begin after start-up has been completed and the desired temperature of the enclosed environment has been achieved, as described below. Additionally, for exemplary purposes, the desired temperature of the enclosed environment 18, with respect to state diagram 300, is 20° C. (68° F.). However, it should be understood that the desired temperature of the enclosed environment 18 can be set to any desired temperature, via programming of the control algorithm. Furthermore, the various milestone and set point temperatures shown in the state diagram 300 are merely exemplary and can be set to any desired temperature, via programming of the control algorithm.

Once the desired set point temperature of the enclosed environment 18, e.g., 20° C. (68° F.), is achieved, the integrated controller board 30, i.e., execution of the control algorithm, turns the compressor motor 114, the heating device(s) 50 and the condenser and evaporator air movers 58 and 70 ‘Off’, as illustrated at state 302. As described above, the temperature of the enclosed environment 18 is monitored using inputs 106 from the evaporator air intake sensor 110A and/or the remote temperature sensor(s) 110H. As the temperature of the enclosed environment 18 increases above the desired set point, the integrated controller board 30 turns the evaporator air mover 70 on and begins to ‘ramp up’ the speed of the evaporator air mover 70 until the temperature of the enclosed environment 18 reaches a high temperature set point, e.g., 30° C. (86° F.), as indicated at state 304. In various embodiments, at the high temperature set point, the evaporator air mover 70 is ‘Full On’. Hysteresis is built into the control algorithm to prevent over-cycling of the VCACS 10. Therefore, the integrated controller board 30 allows the temperature of the enclosed environment 18 to rise a predetermined amount, e.g., 5° C. (41° F.), above the high temperature set point before activating the cooling mode of operation, as indicated at state 306.

Once in the cooling mode, the integrated controller board 30 substantially simultaneously controls the compressor motor 114 and the condenser and evaporator air movers 58 and 70, as described above, to dynamically vary the temperature and/or volume of the evaporator output air flow 102. If an error in the operation of the VCACS 10, and/or the VCACS fails to adequately cool the enclosed environment 18, the integrated controller board 30 activates a high temperature alarm at a predetermined temperature, e.g., 50° C. (122° F.), as indicated at state 308. When cooling properly in the cooling mode, hysteresis allows the VCACS 10 to cool the enclosed environment 18 a predetermined amount, e.g., 5° C. (41° F.), below the high temperature set point before deactivating the cooling mode of operation, as indicated at state 310. Upon deactivation of the cooling mode, the compressor motor 114 and the condenser air mover 58 are turned ‘Off’ while the evaporator air mover 70 continues to run. If the temperature of the enclosed environment 18 continues to fall after the cooling mode is deactivated, the integrated controller board 30 seamlessly transitions the VCACS 10 from the cooling mode to the idle mode. In the idle mode, the evaporator air mover 70 speed is ‘ramped down’ until the enclosed environment 18 temperature falls to the desired temperature set point, at which time the integrated controller board turns the evaporator air mover 70 ‘Off’, as indicated at state 302.

If the enclosed environment 18 temperature falls below the desired temperature set point, e.g., 20° C. (68° F.), the integrated controller board 30 turns the evaporator air mover 70 on and begins to ‘ramp up’ the speed of the evaporator air mover 70 until the temperature of the enclosed environment 18 reaches a low temperature set point, e.g., 10° C. (50° F.), as indicated at state 314. In various embodiments, at the low temperature set point, the evaporator air mover 70 is ‘Full On’. Hysteresis built into the control algorithm allows the temperature of the enclosed environment 18 to fall a predetermined amount, e.g., 5° C. (41° F.), below the low temperature set point before activating the heating mode of operation. When the enclosed environment 18 temperature falls the predetermined amount below the low temperature set point, the integrated controller board 30 seamlessly transitions the VCACS 10 from the idle mode to the heating mode, as indicated at state 316.

Once in the heating mode, the integrated controller board 30 substantially simultaneously controls the heating mechanism(s) 50 and the evaporator air movers 70, as described above, to dynamically vary the temperature and/or volume of the evaporator output air flow 102. If an error in the operation of the VCACS 10, and/or the VCACS fails to adequately heat the enclosed environment 18, the integrated controller board 30 activates a low temperature alarm at a predetermined temperature, e.g., 0° C. (32° F.), as indicated at state 308. When heating properly in the heating mode, hysteresis allows the VCACS 10 to heat the enclosed environment 18 a predetermined amount, e.g., 5° C. (41° F.), above the low temperature set point before deactivating the heating mode of operation, as indicated at state 320. Upon deactivation of the heating mode, the heating mechanism(s) 50 is/are turned ‘Off’ while the evaporator air mover 70 continues to run. If the temperature of the enclosed environment 18 continues to rise after the heating mode is deactivated, the integrated controller board seamlessly transitions the VCACS 10 into idle mode. In the idle mode, the evaporator air mover 70 speed is ‘ramped down’ until the enclosed environment 18 temperature rises to the desired temperature set point, at which time the integrated controller board turns the evaporator air mover 70 ‘Off’, as indicated at state 302.

Thus, the integrated controller board 30 seamlessly transitions operation of the VCACS 10 between the cooling, heating and idle modes to dynamically vary the temperature and/or volume of the evaporator air flow 102 output into the enclosed environment 18 to maintain an approximately constant desired temperature of the enclosed environment 18. More particularly, the integrated controller board 30 seamlessly transitions between substantially simultaneously controlling the compressor motor 114 and the condenser and evaporator air movers 58 and 70 in the cooling mode, controlling the evaporator air mover 70 in the idle mode, and substantially simultaneously controlling the heating mechanism(s) 50 and the evaporator air mover 70 in the cooling mode.

Referring again to FIG. 2, in various embodiments, the processor 122 executes one or more system maintenance algorithms that can be independent algorithms or subroutines of the one or more control algorithms. For simplicity, system maintenance algorithm(s), or subroutine(s) will be referred to herein merely as the maintenance algorithm(s). The maintenance algorithm(s) monitor an operational health status of the VCACS 10, and control the various components to prevent damage to the VCACS 10. For example, to avoid excessive levels of system refrigerant superheat from occurring within the condenser and/or evaporator assemblies 34 and 38, the maintenance algorithm(s) monitor the temperature of the evaporator refrigerant inlet 94 and the evaporator refrigerant outlet 98, via evaporator refrigerant inlet and outlet sensors 110B and 110C. A difference between the evaporator refrigerant inlet 94 and outlet 98 temperatures is used by the maintenance algorithm(s) to estimate the superheat level. If the superheat level is above a desired level, the maintenance algorithm(s) slow down the speed of the evaporator air mover 70 and/or adjust the thermal expansion valve 90 so that less heat from the enclosed environment 18 is absorbed.

In various other exemplary embodiments, the maintenance algorithm(s) is/are executed to monitor a ‘float temperature’ of the condenser heat exchanger 54. The ‘float temperature’ is utilized to insure the pressure of the system refrigerant entering the condenser heat exchanger 54 is not above a desired level. To determine the ‘float temperature’, the maintenance algorithm(s) monitors the temperature of the condenser air flow 82 taken into the condenser heat exchanger 54 and the condenser refrigerant outlet 78, via sensors 110E and 110D. A temperature difference between the condenser air flow 82 intake and the condenser refrigerant outlet 78 is used by the maintenance algorithm(s) to estimate the “float temperature”. If the “float temperature” is above a desired level, the maintenance algorithm(s) reduce the speed of the condenser air mover 58 to maintain the pressure of the system refrigerant entering the condenser heat exchanger 54 approximately at the desired level.

In other various exemplary embodiments, the maintenance algorithm(s) is/are executed to monitor a state estimate of a rotor (not shown) of the compressor motor 114. To determine the state estimate of the rotor, the maintenance algorithm(s) monitors the temperature of the evaporator refrigerant inlet 94 and the condenser refrigerant outlet 78, via sensors 110B and 110D. A temperature difference between the evaporator refrigerant inlet 94 and the condenser refrigerant outlet 78 is used by the maintenance algorithm(s) to determine the state estimate, which is indicative of a pressure difference acting on the compressor 42. Based on the state estimate, the maintenance algorithm(s) can adjust a positional relationship between the compressor motor rotor and a stator of the compressor motor, e.g., a lagging or leading relationship, to maintain optimal function of the compressor 42.

In still other various embodiments, the maintenance algorithm(s) is/are executed to monitor conditions of exterior ambient environment of the VCACS 10 that may be detrimental to the VCACS 10. For example, the maintenance algorithm(s) can monitor the condenser intake air flow 82 temperature, via sensor 110E. A condenser intake air flow 82 temperature above a predetermined temperature may be indicative of a hazardous exterior ambient environment, e.g., a fire in close proximity to the VCACS 110. In such cases, the maintenance algorithm(s) may command all components of the VCACS 110, e.g., the compressor motor 114 and the condenser and evaporator air movers 58 and 70, to shut down to prevent the induction of hazardous conditions, e.g., flames, into the VCACS 10.

In yet other various exemplary embodiments, the maintenance algorithm(s) is/are executed to monitor the temperature of the compressor 42 and/or compressor motor 114 to prevent the compressor 42 and/or compressor motor 114 from overheating. To determine the temperature of compressor 42 and/or compressor motor 114, the maintenance algorithm(s) monitors the inputs 106 from the compressor housing temperature sensor 110F. If the compressor housing temperature is above a predetermined threshold, the maintenance algorithm(s) will increase the speed of the condenser air mover 58 to cool the compressor 42 and/or compressor motor 114.

In still yet other various exemplary embodiments, the maintenance algorithm(s) is/are executed to monitor a temperature of power electronics portion of the integrated controller board 30, e.g., power electronics that drive the compressor motor 114. To prevent overheating of the power electronics portion, the maintenance algorithm(s) monitors the temperature of the heat sink 118, via sensor 110G. If the temperature of the heat sink 118 exceeds a predetermined threshold, the maintenance algorithm(s) will command an increase in the speed of the evaporator air mover 70 and/or command the compressor motor 114 to slow down or totally shut ‘Off’.

In various other embodiments, the maintenance algorithm(s) is/are to monitor the relative humidity of the air flow 102 output by the evaporator assembly 38 to the enclosed environment 18, via the relative humidity sensor 112. A sensed relative humidity of the output air flow 102 above a predetermined threshold, e.g., 100%, is indicative of water condensing on the evaporator heat exchanger 66. To prevent condensation from being blown onto the enclosed environment 18, the maintenance algorithm(s) will decrease speed of the evaporator air mover 70 if the relative humidity of the output air flow 102 is sensed to be above the predetermined threshold.

In other various embodiments, the processor 122 executes an integrated weighted accumulator error detection algorithm for detecting faulty sensors 110 and/or 112. The integrated weighted accumulator error detection algorithm can be an independent algorithm or a subroutine of the one or more control algorithms. The integrated weighted accumulator error detection algorithm determines if any of the sensors 110 and/or 112 are outside a predetermined normal operating range. Each time a particular sensor 110 or 112 provides an erroneous reading, i.e., a reading outside of the normal operating range, an accumulator increments to determine a total sum of errors for that particular sensor 110 or 112. The sum is indicative of a length of time the particular sensor 110 or 112 has been malfunctioning. The larger the total sum in the accumulator, the longer the particular sensor 110 or 112 has been operating outside its normal operating zone. In various embodiments, the integrated weighted accumulator error detection algorithm will reset the accumulator to zero if a predetermined time period elapses between erroneous readings of a particular sensor 110 or 112. Or, in various other embodiments, the integrated weighted accumulator error detection algorithm decrements the accumulator for each valid reading provided by a particular sensor 110 or 112. When the total sum in the accumulator exceeds a predetermined value, the integrated weighted accumulator error detection algorithm activates an alarm, for example, lights an LED on the integrated controller board 30, indicating the particular sensor 110 or 112 need to be repaired of replaced.

In various embodiments, the integrated controller board 30 includes a plurality of status lights 236, e.g., LEDs, (shown in FIG. 5) that can be employed to indicate faulty sensors 110 and/or 112, as determined by the integrated weighted accumulator error detection algorithm. More particularly, in various embodiments, the integrated weighted accumulator error detection algorithm will illuminate certain status lights based on historical status data of each sensor 110 and 112. For example, if the integrated weighted accumulator error detection algorithm senses that a particular sensor 110 or 112 has never had an erroneous reading, a green status light 236 corresponding to the particular sensor 110 or 112 can be illuminated, while a corresponding red status light 236 is not illuminated. However, if the integrated weighted accumulator error detection algorithm has sensed that a particular sensor 110 or 112 has provided one or more erroneous readings, but subsequently functioned properly, the integrated weighted accumulator error detection algorithm can illuminate both corresponding red and green status lights 236. And finally, the total sum in the accumulator for a particular sensor 110 or 112 has exceeded the predetermined value, the integrated weighted accumulator error detection algorithm activates just the corresponding red status light 236.

In still yet other embodiments, a self-diagnostics algorithm is stored on the integrated controller board 30 and can be executed by the processor 122 prior to installing the VCACS 10 in the field. During execution of the self-diagnostics algorithm, the integrated controller board 30 communicates with a peripheral device (not shown) removeably connectable to the integrated controller board 30. Upon execution of the self-diagnostics algorithm the integrated controller board 30 instructs the peripheral device to return various signals simulating various sensor 110 and 112 readings indicating various simulated temperatures of the enclosed environment and/or operation condition of the VCACS 10. In response to the simulated sensor readings, the self-diagnostics algorithm simulates cooling, idle and heating component control commands to simulate operation of the heating and cooling subsystems 22 and 26, as described above. The self-diagnostics algorithm then verifies that the various components of the heating and cooling subsystems 22 and 26, e.g., the compressor motor 114, the condenser and evaporator air movers 58 and 70, and the heating mechanism(s) 50, responded correctly to the commands. Additionally, in various embodiments, the self-diagnostics algorithm tests the system control algorithm to verify the integrity of the system control algorithm.

In yet other embodiments, the VCACS 10 additionally includes a charging dongle 240 (shown in FIG. 5) that is removably connectable to the integrated controller board 30. The charging dongle 240 includes a charging mode software program or algorithm readable by the processor 122 upon connection of the charging dongle 240 to the integrated controller board 30. The charging mode algorithm places the VCACS 10 in a compressor charging mode. More particularly, the charging dongle 240, i.e., the charging mode algorithm, temporarily disables the various components of the VCACS 10, e.g., the condenser and evaporator air movers 58 and 70, while controllably commanding the compressor motor 114 to run, as is needed during the system refrigerant recharging process. Accordingly, if the VCACS 10 requires recharging of the system refrigerant, recharging of the system refrigerant can be performed without having to change temperature set points in the control algorithm in order to cause the compressor motor 114 to operate.

Those skilled in the art can now appreciate from the foregoing description that the broad teachings of the present disclosure can be implemented in a variety of forms. Therefore, while this disclosure has been described in connection with particular examples thereof, the true scope should not be so limited since other modifications will become apparent to the skilled practitioner upon a study of the drawings, specification and following claims. 

1. A direct current (DC) powered variable capacity air conditioning system, said system comprising an integrated controller board configured to substantially simultaneously control a variable speed DC compressor motor, a variable speed condenser air mover and a variable speed evaporator air mover in response to inputs from a plurality of temperature sensors within the system to substantially simultaneously control at least one of a temperature and a volume of an evaporator output air flow of the system.
 2. The system of claim 1, wherein the integrated controller board comprises a compressor motor controller, a condenser air mover controller and an evaporator air mover controller that are controlled by a processor of the integrated controller board.
 3. The system of claim 1, wherein the integrated controller board is configured to execute an operation control algorithm to substantially simultaneously control the variable speed DC compressor motor, the variable speed condenser air mover and the variable speed evaporator air mover.
 4. The system of claim 1, wherein at least one of the variable speed condenser air mover and the variable speed evaporator air mover comprises a backward-curved impeller.
 5. The system of claim 1, wherein the system integrated controller board is located within a path of an evaporator air flow.
 6. The system of claim 1, wherein the variable speed DC compressor motor comprises a variable speed brushless DC motor.
 7. The system of claim 6, wherein the variable speed brushless DC motor comprises a sensorless variable speed brushless DC motor.
 8. The system of claim 1, wherein the system further comprises at least one relative humidity sensor located within an enclosed environment to be air conditioned by the system.
 9. The system of claim 1, wherein the plurality of temperature sensors comprise an evaporator intake air flow sensor, an evaporator refrigerant inlet sensor, an evaporator refrigerant outlet sensor, condenser refrigerant outlet sensor and a condenser intake air flow sensor.
 10. The system of claim 9, wherein the plurality of temperature sensors further comprise at least one of a compressor housing sensor, a controller board heat sink sensor, and at least one remote sensor located within an enclosed environment to be air conditioned by the system.
 11. The system of claim 1, wherein the system further comprises at least one variable output positive temperature coefficient heater controlled by the controller board substantially simultaneously with the variable speed evaporator air mover.
 12. The system of claim 1, wherein the system further comprises a charge mode device removably connectable to the integrated controller board for placing the system in a charging mode.
 13. The system of claim 1, wherein the system further comprises a stepper-motor type electronically variable expansion valve controlled by the integrated controller board based on a sensed temperature of a system refrigerant exiting an evaporator heat exchanger of the system and a sensed temperature of the system refrigerant entering the evaporator heat exchanger.
 14. A method for controlling a temperature within an enclosed environment, said method comprising substantially simultaneously controlling at least one of a temperature and a volume of an evaporator output air flow of a direct current (DC) powered variable capacity air conditioning system utilizing an integrated controller board that uses a plurality of temperature inputs from a plurality of sensors within the system to substantially simultaneously control a variable speed DC compressor motor, a variable speed condenser air mover and a variable speed evaporator air mover, thereby providing a continuum of evaporator output air flow capacities for maintaining an approximately constant temperature within the enclosed environment.
 15. The method of claim 14, wherein substantially simultaneously controlling at least one of the temperature and volume of the evaporator output air flow comprises varying at least one of the temperature and the volume of the an evaporator output air flow in response to the sensor inputs.
 16. The method of claim 14, wherein monitoring inputs comprises receiving as inputs to the integrated controller board, temperature readings of an evaporator intake air flow, an evaporator refrigerant inlet, an evaporator refrigerant outlet, a condenser refrigerant outlet, a condenser intake air flow, a controller board heat sink, a compressor housing and at least one remote location within an enclosed environment to be air conditioned by the air conditioning system.
 17. The method of claim 14, wherein substantially simultaneously controlling at least one of the temperature and the volume of the evaporator output air flow comprises controlling operation of at least one of the variable speed DC compressor motor, the variable speed condenser air mover and the variable speed evaporator air mover when a temperature within the enclosed environment is outside of a desired temperature set point range.
 18. The method of claim 17, wherein the set point range is programmable to temporally vary.
 19. The method of claim 14, wherein substantially simultaneously controlling at least one of the temperature and the volume of the evaporator output air flow comprises controlling operation of the variable speed DC compressor motor, the variable speed evaporator air mover and at least one variable output positive temperature coefficient heater based on the sensor inputs.
 20. The method of claim 14, wherein substantially simultaneously controlling at least one of the temperature and the volume of the evaporator output air flow comprises: determining a superheat state of a system refrigerant at an evaporator refrigerant outlet based on a temperature difference between an evaporator refrigerant inlet and an evaporator refrigerant inlet; and controlling the superheat state by controlling operation of at least one of the variable speed evaporator air mover and a thermal expansion valve of the air conditioning system.
 21. The method of claim 20, wherein the thermal expansion valve comprises a stepper-motor type electronically variable expansion valve and controlling the operation the thermal expansion valve comprises utilizing the integrated controller board to control the stepper-motor type electronically variable expansion valve based on a sensed temperature of the system refrigerant exiting an evaporator heat exchanger of the air conditioning system and a sensed temperature of the system refrigerant entering the evaporator heat exchanger.
 22. The method of claim 14, wherein substantially simultaneously controlling at least one of the temperature and the volume of the evaporator output air flow comprises controlling operation of the variable speed condenser fan to produce a desired float temperature based on a temperature difference between a condenser intake air flow and a temperature of a condenser refrigerant outlet.
 23. The method of claim 14, wherein substantially simultaneously controlling at least one of the temperature and the volume of the of the evaporator output air flow comprises: updating a state estimate of a compressor rotor based on a temperature difference between an evaporator refrigerant inlet and a condenser refrigerant outlet; and controlling operation of the variable speed DC compressor motor based on the updated state estimate.
 24. The method of claim 14, wherein substantially simultaneously controlling at least one of the temperature and the volume of the evaporator output air flow comprises: monitoring a condenser intake air flow temperature to determine environmental conditions exterior to the air conditioning unit that may be detrimental to the air conditioning system; and shutting down the air conditioning system if the exterior environmental conditions are determined to be detrimental.
 25. The method of claim 14, wherein substantially simultaneously controlling at least one of the temperature and the volume of the evaporator output air flow comprises controlling operation of the variable speed condenser air mover based on a compressor housing temperature to prevent the compressor from overheating.
 26. The method of claim 14, wherein substantially simultaneously controlling at least one of the temperature and the volume of the evaporator output air flow comprises: monitoring a temperature of a heat sink of the integrated controller board to determine; and controlling operation of at least one of the variable speed evaporator air mover and the variable speed DC compressor motor, based on the heat sink temperature to prevent a power electronics portion of the integrated controller board from overheating.
 27. The method of claim 14, wherein substantially simultaneously controlling at least one of the temperature and the volume of the evaporator output air flow comprises executing an operation control algorithm, via a processor of the integrated controller board, to substantially simultaneously control the variable speed DC compressor motor, the variable speed condenser air mover and the variable speed evaporator air mover.
 28. The method of claim 14, wherein the method further comprises executing a self-test mode algorithm, via a processor of the integrated controller board, to test functionality of the variable capacity air conditioning system.
 29. A telecommunications station comprising: a direct current (DC) powered variable capacity air conditioning system coupled to a structure enclosing an environment to be thermally conditioned by the DC powered variable capacity air conditioning system, said system comprising: a plurality of temperature sensors; a variable speed DC compressor motor; a variable speed condenser air mover; a variable speed evaporator air mover; and an integrated controller board configured to substantially simultaneously control the variable speed DC compressor motor, the variable speed condenser air mover and the variable speed evaporator air mover in response to inputs from the temperature sensors to substantially simultaneously control at least one of a temperature and a volume of an evaporator output air flow of the system to the enclosed environment.
 30. The station of claim 29, wherein the integrated controller board is configured to execute an operation control algorithm to substantially simultaneously control a compressor motor controller, a condenser air mover controller and an evaporator air mover controller to substantially simultaneously control the variable speed DC compressor motor, the variable speed condenser air mover and the variable speed evaporator air mover.
 31. The station of claim 29, wherein the variable speed DC compressor motor comprises a sensorless variable speed brushless DC motor.
 32. The station of claim 29, wherein the plurality of temperature sensors comprise an evaporator intake air flow sensor, an evaporator refrigerant inlet sensor, an evaporator refrigerant outlet sensor, condenser refrigerant outlet sensor and a condenser intake air flow sensor.
 33. The station of claim 29, wherein the system further comprises at least one variable output positive temperature coefficient heater controlled by the controller board substantially simultaneously with the variable speed evaporator air mover.
 34. The station of claim 29, wherein the system further comprises a charge mode device removably connectable to the integrated controller board for placing the system in a charging mode.
 35. A direct current (DC) powered variable capacity air conditioning system, said system comprising: a variable speed DC compressor; and a controller board configured to operate the variable speed DC compressor at varying speeds during operation of the variable capacity air conditioning system.
 36. The system of claim 35, wherein the variable speed DC compressor comprises a sensorless variable speed brushless DC motor. 